https://en.wiktionary.org/wiki/bix_nood

From a comic by the cartoonist A. Wyatt Mann, which depicts a black man speaking in gibberish. It was later reuploaded by users of the 4chan image board /b/. It has no known discernible etymological root.

Not going to link the original comic since it's wildly racist. But the same guy who drew the happy merchant meme drew this cartoon depicting a black woman badly.